The Community Practice Research Core, formerly the Community Practice Core, enables Dana-Farber/Harvard Cancer Center researchers to conduct cancer-related projects in real-world community settings. The Core provides easy access to a racially diverse population of over 11,000,000 patients within the local and national community-based clinical practices of Harvard Vanguard Medical Associates (HVMA)/Atrius Health, Harvard Pilgrim Health Care and HMO Cancer Research Network. Harvard Vanguard Medical Associates is a non-profit, multi-specialty medical group practice providing care to more than 480,000 adult and pediatric patients at over 21 offices across eastern Massachusetts. It is one of five medical groups that comprise Atrius Health. All Atrius groups share a single electronic medical record system (EPIC?), easing researchers' access to its 600,000 patients. Harvard Pilgrim Health Care is a non-profit health plan that provides medical insurance to more than 1,000,000 members in Massachusetts, New Hampshire and Maine. Cancer Research Network is an NCI-funded consortium of 14 integrated healthcare systems, representing 11,000,000 enrollees across the United States. This facility has been continuously funded by the CCSG since 2000. Director: Larissa Nekhlyudov, MD, MPH(HMS) Category: 3.01, 3.03 and 3.06 (Population Research) Management: Cancer Center managed.